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Published in final edited form as: Artif Organs. 2022 Mar 17;46(8):1597–1607. doi: 10.1111/aor.14226

Isolated Left Ventricular Assist Device Implantation Produces Variable Changes to Patient Body Mass Index

Sonal R Chandratre 1, Nathan J Smith 2, Richard W Walsh 3, Tammy Kindel 4, Sakthi K Sundararajan 5, David L Joyce 2,*, Asim Mohammed 6
PMCID: PMC9256767  NIHMSID: NIHMS1795211  PMID: 35261065

Abstract

Background:

Body Mass Index (BMI) is an important consideration for transplant-eligible Left Ventricular Assist Device (LVAD) recipients. LVAD therapy’s impact on BMI is unclear. We evaluated BMI changes in patients who underwent LVAD implantation. The association between these patients’ BMI and transplant was studied.

Methods:

This was a retrospective cohort study of patients who underwent LVAD implantation between January 1, 2012-December 31, 2018 at our institution. Patients were stratified by preoperative BMI (kg/m2) into 4 groups: < 30, 30–34.9, 34.9–39.9, and ≥40. BMI data was collected at 12 and 6 months prior to implant, time of implantation, and 3- and 6- months post-implantation.

Results:

107 patients underwent LVAD implantation at our institution. Data was available for 80 patients. Baseline characteristics included mean age 56.0 years, 69% male, and mean implant BMI 29.9 ± 6.8 kg/m2. The mean BMI (kg/m2) with each of the BMI (kg/m2) groups <30, 30–34.9, 35–39.9, and ≥ 40 (n= 60, 25, 12, 10 respectively) was 25.1., 32.5, 36.8, and 43.8, respectively. There was no consistent pattern with weight change across differing implant BMIs. No patient with a BMI of <30 gained sufficient weight to impact transplant candidacy. 23% of patients with BMI of 30–34.9 kg/m2, 60% of patients with a BMI 35–39.9 kg/m2, and 87.5% of patients with a BMI of ≥40 had a 6-month BMI potentially affecting transplant.

Conclusions:

Associated weight changes during LVAD support may significantly impact transplant candidacy. Higher BMI groups may benefit from multimodal and multidisciplinary targeted weight-loss interventions.

Keywords: Heart failure; LVAD, left ventricle assist device; BMI, body mass index; MCS, mechanical circulatory support; Obesity; Transplant; Weight loss; Bariatric surgery; Destination therapy; Morbid obesity; Class 2 obesity; Class 3 obesity

Introduction:

Obesity continues to be a growing public health problem in the United States with the number of obese patients climbing at an alarming rate (1). Obesity is a well-known risk factor for the development of cardiovascular disease and heart failure (2, 3). For patients who require advanced heart failure therapies, obesity not only impacts overall prognosis, but significantly limits the number of available treatment options. Morbidly obese patients have the highest rates of mortality after LVAD implant (4). Class 2 and 3 patients have traditionally been excluded from consideration for cardiac transplantation (5), with the International Society for Heart and Lung Transplant (ISHLT) guidelines recommending a Body Mass Index (BMI) <35 kg/m2 for candidacy (6). When LVAD patients with obesity are listed as a bridge to transplant (BTT) they are less likely to find an appropriate donor (7) and have higher post-transplant morbidity and mortality (6). While there is also some evidence suggesting that class 1 obesity (BMI 30–34.9 kg/m2) has a significant positive effect on post-transplant mortality, patients with class 2 and 3 obesity (BMI ≥ 35 kg/m2) demonstrate a significant higher post-transplant mortality (8).

Theoretically, LVAD implantation may allow for weight loss through symptom relief via increased exercise capacity and tolerance (9–11). However, current data is variable with reports of LVAD implantation associated with weight gain (12, 13) while others reporting weight loss (6, 14). Although this has been studied prior, to date there has been no study of BMI change after LVAD implant involving multiple LVAD models. We sought to investigate the impact of LVAD implantation on patient BMI in obese patients (BMI > 35 kg/m2) with end-stage heart failure. We hypothesized that LVAD implantation in most patients would fail to reduce BMI at 6 months after implant when compared to the BMI at implant

Material and Methods:

Our study was a retrospective cohort study of all adult patients that had undergone durable LVAD implantation between 1/1/2012 and 12/31/2018 at our academic medical center in Southeastern Wisconsin. Institutional Review Board approval was obtained, and patient data was collected through review of the electronic medical record.

Patients were stratified into four groups based on BMI (kg/m2) at the time of implantation: < 30, 30–34.9, 35–39.9, and ≥ 40. We collected patient demographics, clinical characteristics, mortality data, and BMI data at 12 and 6 months prior to implant, time of implant, and 3- and 6- months post-implant. The primary endpoint was BMI change at 6 months after implant. Secondary outcomes included movement from one BMI group to another at the end of 6 months after implant and mortality. All BMI changes were calculated using BMI at the time of LVAD implantation as the reference point.

Categorical variables are expressed as the number of individuals (percentage) and continuous variables as mean ± standard deviation (SD) with analysis of variance and chi squared testing performed. A scatter plot was used to visualize the correlation between weight difference changes over time. Additional lines were overlaid on the plots to indicate the trend of the correlation. Box plots were used to display patterns of weight difference over time within each BMI Implant group. Mixed effects model was performed to estimate the association between weight difference and other variables (time, BMI Implant). Bar plots were performed to show the move from a lower than BMI of 35 kg/m2 at time of implant to a higher than BMI of 35 kg/m2 after 6 months post procedure and the move from a higher than BMI of 35 kg/m2 at the time of implant to a lower than BMI of 35 kg/m2 after 6 months post procedure. Fisher’s exact test and Cochran-Armitage trend test were used to evaluate whether the probability of having BMI above 35 kg/m2 varied by the BMI category at implant. McNemar’s test was used to test if change from under BMI of 35 kg/m2 to over BMI of 35 kg/m2 was as likely as the reverse change. Kaplan-Meier Survival Plot and log-rank test were used to compute the survival over time and visualize the difference of the survival among BMI Implant groups.

Results:

A total of 107 patients underwent LVAD implantation over the course of the study period. Baseline characteristics are detailed in Table 1. Age and sex were not significantly different between BMI subgroups. Comorbidities and preoperative laboratory values were not significantly different except for diabetes, hypertension, aspartate aminotransferase, and blood urea nitrogen as detailed in Table 1. Most patients in the BMI <30 kg/m2, 30–34.9 kg/m2 and 40+ kg/m2 subgroups were implanted as a bridge-to-transplant (BTT) strategy. The mean BMI at the time of implant for the overall population was 29.9 ± 6.8 kg/m2. Six-month post implant data was available 80 (74.8%) of patients, specifically, : 46 (42.9%) patients with a BMI of <30 kg/m2, 17 (15.8%) BMI 30–34.9 kg/m2, 10 (9.3%) BMI 35–39.9 kg/m2, and 7 (6.5%) BMI ≥ 40 kg/m2.

Table 1:

Preoperative Demographics and Characteristics for LVAD patients

BMI at Implant
Variables Total N=107 < 30 N=60 30–34.9 N=25 35–39.9 N=12 40+ N=10 p-value
Age 56.0 ± 12.0 56.8 ± 12.5 57.5 ± 9.0 55.2 ± 8.1 48.4 ± 17.1 0.194 **
Male 74 (69.2) 45 (75.0) 16 (64.0) 9 (75.0) 4 (40) 0.146 *
BMI at Implant
 Mean ± SD 29.9 ± 6.8 25.1 ± 3.1 32.5 ± 1.6 36.8 ± 1.4 43.8 ± 4.3 <.001 **
 Median (min, max) 28.7 (18.7,53.3) 25.6 (18.7,29.9) 32.6 (30.0,34.9) 36.4 (35.0,39.2) 41.8 (40.0,53.3)
LVAD Type
 HVAD 83 (77.6) 46 (76.7) 19 (76.0) 11 (91.7) 7 (70.0)
 Heart mate II 13 (12.1) 8 (13.3) 2 (7.69) 1 (8.33) 2 (20.0)
 Heart mate III 11 (10.2) 6 (10.0) 4 (15.4) 0 (0.00) 1 (10.0)
Bridge to Transplant 34 (56.7) 19 (76.0) 4 (33.3) 5 (50.0)
Comorbidities
  Coronary Artery Disease 42 (39.3) 18 (30.0) 16 (64.0) 6 (50.0) 2 (20.0) 0.012 *
  Diabetes Mellitus 51 (47.7) 20 (33.3) 17 (68.0) 10 (83.3) 4 (40.0) 0.001 *
  Hypertension 44 (41.1) 19 (31.7) 14 (56.0) 8 (66.7) 3 (30.0) 0.040 *
  Atrial Fibrillation 27 (25.2) 11 (18.3) 10 (40.0) 4 (33.3) 2 (20.0) 0.177 *
  Hyperlipidemia 39 (35.5) 16 (26.7) 12 (48.0) 6 (50.0) 4 (40.0) 0.176 *
  Chronic Kidney Disease 15 (14.0) 7 (11.7) 5 (20.0) 2 (16.7) 1 (10.0) 0.777 *
  Stroke 7 (6.5) 2 (3.3) 2 (8.0) 1 (8.3) 2 (20.0) 0.209 *
Albumin (g/dL) 3.6 ± 0.6 3.5 ± 0.5 3.6 ± 0.7 3.7 ± 0.6 3.5 ± 0.5 0.681 **
Cardiac Output (Fick) (L/min) 4.0 ± 1.3 3.7 ± 1.1 4.5 ± 1.6 4.5 ± 1.4 3.9 ± 1.2 0.058 **
Cardiac Index (L/min/m2) 1.93 ± 0.57 1.93 ± 0.59 2.05 ± 0.63 1.94 ± 0.44 1.59 ± 0.38 0.260 **
AST (units/L) 127.3 ± 672.2 40.5 ± 34.9 46.2 ± 53.1 705.3 ± 2048.4 252.2 ± 558.5 0.027 **
BUN (mg/dL) 25.8 ± 15.2 22.9 ± 13.9 27.5 ± 15.8 36.3 ± 16.1 26.0 ± 16.2 0.037 **
Creatinine (mg/dL) 1.34 ± 0.61 1.25 ± 0.51 1.32 ± 0.41 1.59 ± 0.57 1.66 ± 1.24 0.097 **
Glucose (mg/dL) 128.9 ± 42.8 127.4 ± 46.3 131.6 ± 30.9 129.5 ± 39.5 130.2 ± 55.6 0.980 **
Glycohemoglobin (%) 6.4 ± 1.3 6.2 ± 1.2 6.6 ± 0.8 6.8 ± 1.9 6.9 ± 2.0 0.300 **
Hemoglobin (g/dl) 10.8 ± 1.9 10.8 ± 1.9 10.4 ± 1.6 11.0 ± 2.2 11.1 ± 2.5 0.685 **
Serum sodium (mmol/L) 136.0 ± 4.5 135.2 ± 4.7 137.3 ± 4.0 136.8 ± 3.1 136.5 ± 5.5 0.207 **
Platelet count (×103) 207.8 ± 108.8 219.9 ± 127.4 177.2 ± 76.0 216.2 ± 78.7 201.4 ± 79.9 0.423 **
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*

Chi-square test

**

ANOVA F-test

Changes in weight among the groups was statistically significant at 3 months before their LVAD implantation (p=.003) and 3 months post implant (p< 0.001) (Table 2). In the BMI (kg/m2) group of 30–34.9, the group’s greatest weight loss came at 3 months post implantation with an average loss of 7.3 kg compared to their weight at implantation. To contrast, at 6 months post implant, the average weight loss for this groups was 5 kg when compared to the time of implantation. There were no statistically significant changes at 6 months post-implant for weight or BMI in LVAD patients, regardless of implant indication, when compared to initial BMI at implant (Table 1).

Table 2:

Change in Weight (kg) for LVAD Patients at Compared to Weight at Implant

BMI at Implant
Time Point Total N=80 < 30 N=46 30–34.9 N=17 35–39.9 N=10 40+ N=7 p-value
1 year before Implant 3.6 ± 10.7 7.2 ± 7.9 1.2 ± 10.7 3.6± 14.3 −5.6 ± 11.1 0.024 **
6 months before Implant 1.4 ± 9.0 5.8 ± 6.3 0.1 ± 9.1 −1.6 ± 7.2 −7.1 ± 11.0 0.003 **
3 months after Implant −2.1 ± 7.2 0.6 ± 6.0 −5.5 ± 7.0 −7.3 ± 7.8 −5.1 ± 6.5 <.001 **
6 months after Implant −1.6 ± 10.1 0.9 ± 9.0 −5.6 ± 11.2 −5.0± 10.4 −3.7 ± 11.2 .072 **
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**

ANOVA F-test

The change in weight (kg) of a patient when visualized in box plots for the whole population is detailed in Figure 1. The same date for exclusively BTT patients was also visualized in a box plot (Figure 2) as well as the data for destination therapy (DT) patients (Figure 3). There were no statistically significant differences in weight after LVAD implantation in the population as a whole or when broken down into BTT or DT groups. This held true even when the group was broken down based on implant BMI

Figure 1: Box Plot Demonstrating Weight change (kg) from 1 year prior to Implant to 6 months Post Implant Separated by BMI at Implant.

Figure 1:

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Figure 2: Box Plot Demonstrating Weight change (kg) from 1 year prior to Implant to 6 months Post Implant Separated by BMI at Implant from Bridge to Transplant Patients.

Figure 2:

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Figure 3: Box Plot Demonstrating Weight Change (kg) from 1 year prior to Implant to 6 months Post Implant Separated by BMI at Implant for Destination Therapy Patients.

Figure 3:

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The percentage of patients implanted as a BTT receiving a transplant for each of the groups is detailed in Figure 4. No patients in the BMI of 35–39.9 kg/m2 received a transplant. The number of patients in each group with a BTT strategy were 34 (57%), 19 (76%), 4 (33%), and 5 (50%) for the < 30 kg/m2, 30–34.9 kg/m2, 35–39.9 kg/m2, and > 40 kg/m2 groups, respectively. Of these same groups with a BTT plan, the number of patients transplanted was 18 (53%), 11 (58%), 0, and 1 (20%). The highest proportions of transplantation were in the < 30 kg/m2 and 30–34.9 kg/m2 BMI groups. When including both BTT and DT treatments, 100% and 76.5% of the < 30 kg/m2 and 30–34.9 kg/m2 BMI groups, respectively, successfully maintained a 6-month post-implant BMI < 35 kg/m2. 40% and 14.3% (n=1) of patients in the 35–39.9 and 40+ kg/m2 BMI groups, respectively, lost enough weight to achieve a 6-month post-implant BMI <35 kg/m2. No patients in the group of 35–39.9 kg/m2 were successfully transplanted.

Figure 4: Movement To/From BMI of 35 After 6 months Based on Implant BMI and Percentage of BTT Patients Transplanted.

Figure 4:

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There was no significant difference in Kaplan-Meier survival between BMI subgroups post-implantation (Log-rank p=0.4102) (Figure 5). There is a trend for increased mortality in the BMI of 35–39.9 kg/m2 group compared to others.

Figure 5: Kaplan-Meier Survival Curve for LVAD patients based on Implant BMI.

Figure 5:

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A table with the type of LVAD device (HVAD™, Heartmate II™, and Heartmate III™) is presented, and there was no statistically significant effect on weight gain or loss (Supplemental Table 1). The total number of patients that had an LVAD at time 6 months was 62. A total of 21 patients suffered mortality, 18 were lost to follow up, and 8 were transplanted.

A visual representation of the cohort split into groups first via implantation BMI then by treatment strategy is provided in the supplementary material (Supplemental Figure 1).

The percentage of patients in each implantation BMI group that were assigned to either BTT or DT is displayed (Supplemental Figure 2). Further, the percentage of these patients above or below the 35 kg/m2 benchmark is present for all patients assigned to a BTT treatment plan (Supplemental Figure 3) or DT plan (Supplemental Figure 4).

Line plots demonstrated weight change in kg from 2 years prior to LVAD to 6 months post procedure for the population as a whole (Supplemental Figure 5) and for all patients assigned to a BTT treatment plan (Supplemental Figure 6) or DT plan (Supplemental Figure 7).

Discussion

In this study, we evaluated the impact of LVAD implantation on BMI 1-year prior implantation to 6-months post-implantation. The present study sought to profile the impact of LVAD implantation on BMI and weight and to observe any benefit or detriment to transplant candidacy based on BMI. BMI has long been a factor in organ transplantation candidacy. Current ISHLT guidelines for heart transplantation suggest a BMI < 35 for patients to be considered eligible (8). The data presented here suggest that patients’ BMI response to LVAD therapy is variable. The greatest weight loss happened at 3 months after LVAD implantation surgery, but was no longer significant by 6 months post-implantation. Meeting the 35 kg/m2 BMI cutoff varied for those with an implant BMI of 30–39.9 kg/m2. In the group with an implant BMI 30–34.9 kg/m2, 23.5% of patients gained significant weight to surpass the ISHLT transplant-eligible BMI. This demonstrates a failure of treatment if the goal of these patients was maintaining a transplant-eligible BMI. Within the implant BMI of 35–39.9 kg/m2 group, 40% of patients lost enough weight to meet the transplant cutoff. This group demonstrates a population that can potentially be rescued from DT and reclaimed for transplant; however none were transplanted at 6-month post-implant. Of those with an implant BMI of over ≥40+ kg/m2, 85.7 % failed to meet a transplant-eligible BMI. All patients with a BMI of under 30 kg/m2 successfully met a transplant-eligible BMI at 6 months post-implantation. As the BMI at the time of implant increased, the percentage of patients transplanted successfully with an initial BTT plan was variable, but followed a trend towards less patients transplanted after the implant BMI exceeded 35 kg/m2. There was an increase in transplant rate in the 30–34.9 BMI group (57.8%) compared to the BMI < 30 group (52.9%). The only exception was a 20% success rate of the 40+ BMI group (n=5) as this group had a BTT treatment plan strategy, but the transplant rate decreased as the patient implant BMI increased.

The survival of post-op LVAD patients in this study did not vary based on the BMI at the time of implantation as demonstrated in Figure 5 (p=0.4102). Although there did appear to be a trend for patients within the BMI group of 35–39.9 kg/m2 for poorer survival, this change was not statistically significant. Survival rates after LVAD surgery are a topic of controversy including evidence that morbidly obese patients suffer more complications (15). There is also evidence demonstrating BMI at the time of surgery has no effect on mortality (16). There is a phenomenon described as the “obesity paradox” where patients in heart failure tend to have better survival with moderate levels of obesity for uncertain reasons (17). Although there was no statistically significant difference in survival of patients based on their BMI at the time on LVAD implant, there was a potential trend that mirrored this obesity paradox (18, 19) as is noted in Figure 5. Given this potential for a trend, further study to determine if the “obesity paradox” exists in LVAD patients is also required. If present, this advantage fails as patients enter higher classes of obesity as demonstrated by our BMI of 35–39.9 kg/m2. Additionally, this group has a statistically higher incidence of type 2 diabetes and hypertension providing evidence that their comorbidities may have played a larger role in their poor survival. It is also noted that bariatric surgery in these patients may lead to resolution of both hypertension and type 2 diabetes mellitus (20). The patients in the BMI of 40 kg/m2 and above had a lower incidence of comorbidities and possibly more intensive obesity treatment, given the largest weight loss pre-op of any group evidenced in Table 1.

Patients risk weight gain after LVAD implant (12–14). One possible etiology may be the role of a poorly perfused gastrointestinal tract during heart failure. Poor gastrointestinal perfusion due to severe heart failure fails to provide adequate digestion and nutrient absorption which is evident in the malnourished and cachexic state many heart failure patients present in. This phenomenon is often referred to as the “cardiointestinal syndrome” and has a role in the pathogenesis of heart failure (21). After LVAD implant, perfusion improves and there may be a rebound effect as the gastrointestinal tract achieves adequate perfusion and improved absorptive capacity. LVAD implantation also corrects metabolic derangements including GH/IGF-1 signaling that should theoretically improve weight loss (22)

Another possible reason is the cumbersome nature of the LVAD device which may hinder exercise with the multiple batteries and equipment required to be carried everywhere by the user. There were 3 types of devices utilized in the patient population: the HVAD™ device by Medtronic, Heartmate II™, and Heartmate III™, both by Abbott. The most common LVAD was the HVAD™ at 77% of the population, and then the Heartmate II™ and Heartmate III™ at 12% and 10% respectively. There was no statistically significant relationship between the specific device and gain or loss of BMI. This is further illustrated in supplemental table 1. All devices had multiple components including the device with drive line, batteries, extra batteries, and charging apparatus. The LVAD alone likely makes exercise more difficult and may also contribute to potential weight gain even though there is evidence the LVAD increases exercise tolerance (9).

Considering the role that BMI has in transplant candidacy, appropriate weight control now becomes an important factor for successful transplant (23). The role of bariatric surgery in heart failure patients, specifically LVAD patients and transplant candidates, is growing. Prior to implantation, it is possible for patients to consult with a bariatric surgeon and complete prerequisites required for bariatric surgery candidacy, either during LVAD candidacy evaluation or after implantation. In some cases, it is possible for some obese patients to lose enough weight to both be transplanted and also to potentially improve their outcomes (14). There are reported cases of bariatric surgery and LVAD implantation leading to weight loss resulting in successful transplant. (24–27). Both staged and simultaneous approaches to bariatric surgery and LVAD implantation have demonstrated favorable outcomes concluding that bariatric surgery has opened the potential to transplant in patients that otherwise were ineligible from morbid obesity (25). Although these invasive options prove successful, there is also evidence that a non-invasive diet program has efficacy in managing weight after LVAD implant (12).

The non-surgical treatment of obesity for patients with mechanical circulatory support (MCS) devices can be especially challenging due to complex medical co-morbidities, dietary restrictions, and polypharmacy. Further, patients with severe obesity and heart failure carry increased perioperative risk compared to non-heart failure patients (28). However, bariatric surgery may be the only option for this group of patients for long-term cardiovascular mortality reduction or a weight loss bridge to cardiac transplantation.

Given the interplay between heart failure and obesity, our institution has developed a program that has taken a multi-disciplinary surgical and non-surgical approach to weight-loss based on both patient and provider goals of care that we would like to share as an effective strategy to reach a BMI to cardiac transplant listing.

Most patients with severe obesity referred to the Comprehensive Bariatric Surgery & Medical Weight Loss Program at our academic medical center have a primary goal of referral to reach a BMI of 38 kg/m2 at our center to qualify for heart transplant listing. If the patient is interested in weight loss only to achieve transplant listing with no other weight loss motivators, we consider patients for medical weight loss if their BMI is ≤42 kg/m2. Studies have shown that even with intense medical weight loss (including pharmacotherapy which is often contraindicated in heart failure patients), achieving a BMI loss of over 10% long-term, not just short-term, is highly unlikely (29). Non-surgical weight loss at our program includes at least monthly visits with providers specializing in obesity care and weight loss pharmacotherapy, clinical dieticians, health psychologists, and enrollment in an exercise program with either an exercise physiologist or formal cardiac rehabilitation. For patients who have (1) a BMI over 38 who desire not just weight loss for transplant listing but also improved medical comorbidities (e.g. type 2 diabetes, obstructive sleep apnea, hypertension) and quality of life, or (2) patients who need more than 4 points of a BMI loss for heart transplant eligibility, we highly recommend consideration for bariatric surgery. This program includes all components of the non-surgical weight loss pathway but also involvement of a bariatric surgeon, dieticians and health psychologists. Given the increased morbidity and mortality of operating on patients with severe obesity and MCS, it is imperative that the hospital system infrastructure support intense pre-operative cardiac and medical optimization to lower the perioperative risk. Depending on the surgical procedure selected, a BMI drop of 12 points by one year can be expected (30). Therefore, although we still consider patients for bariatric surgery with a BMI over 50 kg/m2 with MCS, it is important that counseling includes realistic weight loss goals and the potential for transplant listing and identify other motivating factors for bariatric surgery to ensure there is appropriate patient clinical benefit compared to surgical risk.

Existing literature and our institution’s first-hand experience has demonstrated successful transplants in obese patients after interventions. This concurs with a systematic meta-analysis of 11 studies with 98 patients that found bariatric surgery as a safe and effective method to achieve heart transplant and weight loss in end stage heart failure patients. The optimal method of bariatric surgery and long-term outcomes are areas of research requiring further investigation (31). Another future consideration is for centers to utilize BMI as a controlled value in LVAD patients. BMI control could be utilized as a criterion similar to anticoagulation, diabetes, and other conditions that are well controlled for in these patients as part of a bridge to transplant plan. Additionally, just as adverse events including stroke and emboli contribute to poor outcome, failure to transplant on a BTT plan also provides a poor outcome when compared to patients who undergo successful transplant (32). Perhaps including morbid obesity as an adverse event of LVAD implant may provide a means to further track the effect LVADs or treatment plans have on morbid obesity and transplant candidacy loss.

Should these methods prove successful as they have prior, this can provide an opportunity to rescue these patients from DT and open the opportunity to transplant, associated with the lowest mortality in heart failure, for this population.

Our study has several notable limitations. The sample size is relatively small with a total of 80 patients with complete data. We followed up our patients only up to 6 months after LVAD implant and though unlikely, there is still a possibility for major weight changes after this period that may have been a direct result of LVAD implant. There are some differences in hemodynamic profiles in the different groups expected. Noted in Table 1, the incidence of diabetes mellitus and concomitant decrease in renal function tends to increase as the BMI of the patient increases. This trend is anticipatory in coronary artery disease. Certain other diseases may have potentially affected weight fluctuations that were not elucidated, but that could be explained by the hemodynamic differences in Table 1. Considering the variability seen in Figure 2, there is a potential that healthcare team differences in motivation or approaches may have allowed certain patients to lose weight more than other patients. There is also the potential for other factors not assessed including potential effects of mental health on the patients, social determinants of health, or support structure around patients which is important for weight loss and long-term care.

The data here suggests BMI response to LVAD therapy is variable. Patients with BMI range of 30–34.9 kg/m2 and 35–39.9 kg/m2 had potential to move into and out of the transplant BMI target of under 35 kg/m2. Groups with BMI of ≥40 kg/m2 had only one patient successfully losing enough weight to fall below a BMI of 35 kg/m2 and resulting in transplant. There was no statistical correlation between LVAD implant when compared to change in BMI over time or BMI at 6 months post implant. The data suggests that LVAD implant alone fails to provide weight gain or loss apart from other factors. These may include both surgical and non-surgical intervention to evaluate if they provide sufficient weight loss for patients to meet the transplant cutoff BMI of 35 kg/m2.

Based on our treatment experiences with LVAD patients, our recommendations include an algorithm with incrementally more aggressive treatments over time individualized to each patient and case through utilizing a treatment team. The first step begins in the cardiology or transplant clinic and is initiated by the transplant team. Considering the increase in heart failure patients with obesity, understanding how to achieve successful weight loss in this population provides an achievable and impactful opportunity to reclaim patients who otherwise face eventual mortality on destination therapy.

Supplementary Material

fS2

Supplemental Figure 2: Percentage of LVAD Patients Assigned to Either Bridge to Transplant or Destination Therapy based on Implant BMI

fS1

Supplemental Figure 1: Break Down of LVAD Patients via Implantation BMI, Treatment plan, and Transplant Success

fS3

Supplemental Figure 3: Movement To/From Transplant BMI of 35 After 6 months Based on Implant BMI for Patients with a Bridge to Transplant Plan.

fS4

Supplemental Figure 4: Movement To/From Transplant BMI of 35 After 6 months Based on Implant BMI for Patients on Destination Therapy

fS5

Supplemental Figure 5: Scatter Plot Demonstrating Weight change (kg) from 1 year prior to Implant to 6 months Post Implant Separated by BMI at Implant

tS1

Supplemental Table 1: LVAD Devices and BMI Changes by Device Type

fS6

Supplemental Figure 6: Scatter Plot Demonstrating Weight change (kg) from 1 year prior to Implant to 6 months Post Implant Separated by BMI at Implant from Bridge to Transplant Patients

fS7

Supplemental Figure 7: Scatter Plot Demonstrating Weight Change (kg) from 1 year prior to Implant to 6 months Post Implant Separated by BMI at Implant for Destination Therapy Patients

Acknowledgements:

Special thanks to the Cardiothoracic surgery team at the Medical College of Wisconsin including Dr. Lyle Joyce, Dr. Lucian Durham III, and Dr. Paul Pearson for their feedback on portions of this project earlier on and Department of Surgery physician Dr. Michael Cain for his contributions earlier on in the project. We would also like to extend a thanks to the departmental staff including research nursing and biostatistical services especially Dr. Aniko Szabo.

Funding:

The present study was funded with departmental funds from the Department of Surgery, Division of Cardiothoracic Surgery at the Medical College of Wisconsin, Milwaukee, WI. Dr. Kindel is funded by the NIH/NHLBI K08 HL140000, an American College of Surgeons George Clowes Career Development Award, a Medical College of Wisconsin Research Affairs Committee Award, and the Medical College of Wisconsin Cardiovascular Center Michael Keelan Jr. MD Research Foundation Award.

Glossary of Abbreviations:

LVAD

left ventricle assist device

BMI

body mass index

MCS

mechanical circulatory support

BTT

bridge to transplant

DT

destination therapy

Footnotes

Conflicts of Interest/Disclosures:

David L. Joyce has the following conflicts of interest unrelated to this research: Abiomed- consultant and LivaNova (Prior Tandemlife) - consultant

All the other authors listed have no conflicts of interest to disclose in the submission of this manuscript.

IRB number and approval date: PRO00032395, approved 06/05/2018

References

  • 1.Andolfi C, Fisichella PM. Epidemiology of Obesity and Associated Comorbidities. Journal of Laparoendoscopic & Advanced Surgical Techniques. 2018;28(8):919–24. [DOI] [PubMed] [Google Scholar]
  • 2.Reddy YNV, Melenovsky V, Redfield MM, Nishimura RA, Borlaug BA. High-Output Heart Failure: A 15-Year Experience. J Am Coll Cardiol. 2016;68(5):473–82. [DOI] [PubMed] [Google Scholar]
  • 3.Kenchaiah S, Evans JC, Levy D, Wilson PW, Benjamin EJ, Larson MG, et al. Obesity and the risk of heart failure. N Engl J Med. 2002;347(5):305–13. [DOI] [PubMed] [Google Scholar]
  • 4.Benjamin MM, Sundararajan S, Sulaiman S, Kindel T, Joyce D, Mohammed AA. Testing the obesity paradox in patients on long-term milrinone infusion for end-stage heart failure. Am J Cardiovasc Dis. 2019;9(4):59–64. [PMC free article] [PubMed] [Google Scholar]
  • 5.Clerkin KJ, Naka Y, Mancini DM, Colombo PC, Topkara VK. The Impact of Obesity on Patients Bridged to Transplantation With Continuous-Flow Left Ventricular Assist Devices. JACC: Heart Failure. 2016;4(10):761–8. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 6.Mehra MR, Canter CE, Hannan MM, Semigran MJ, Uber PA, Baran DA, et al. The 2016 International Society for Heart Lung Transplantation listing criteria for heart transplantation: A 10-year update. The Journal of Heart and Lung Transplantation. 2016;35(1):1–23. [DOI] [PubMed] [Google Scholar]
  • 7.Weiss ES, Allen JG, Russell SD, Shah AS, Conte JV. Impact of recipient body mass index on organ allocation and mortality in orthotopic heart transplantation. J Heart Lung Transplant. 2009;28(11):1150–7. [DOI] [PubMed] [Google Scholar]
  • 8.Russo MJ, Hong KN, Davies RR, Chen JM, Mancini DM, Oz MC, et al. The Effect of Body Mass Index on Survival Following Heart Transplantation: Do Outcomes Support Consensus Guidelines? Annals of Surgery. 2010;251(1):144–52. [DOI] [PubMed] [Google Scholar]
  • 9.Nd Jonge, Kirkels H Lahpor JR, Klöpping C Hulzebos EJ, ABdl Rivière, et al. Exercise performance in patients with end-stage heart failure after implantation of a left ventricular assist device and after heart transplantation. Journal of the American College of Cardiology. 2001;37(7):1794–9. [DOI] [PubMed] [Google Scholar]
  • 10.Scheiderer R, Belden C, Schwab D, Haney C, Paz J. Exercise guidelines for inpatients following ventricular assist device placement: a systematic review of the literature. Cardiopulm Phys Ther J. 2013;24(2):35–42. [PMC free article] [PubMed] [Google Scholar]
  • 11.Morrone TM, Buck LA, Catanese KA, Goldsmith RL, Cahalin LP, Oz MC, et al. Early progressive mobilization of patients with left ventricular assist devices is safe and optimizes recovery before heart transplantation. J Heart Lung Transplant. 1996;15(4):423–9. [PubMed] [Google Scholar]
  • 12.Vandersmissen K, Driesen J, Van den Bossche K, Droogne W, Jacobs S, Fresiello L, et al. Do LVAD Patients Need a Specific Diet to Control Weight? The Journal of Heart and Lung Transplantation. 2017;36(4):S176–S7. [Google Scholar]
  • 13.Emani S, Brewer RJ, John R, Slaughter MS, Lanfear DE, Ravi Y, et al. Patients with low compared with high body mass index gain more weight after implantation of a continuous-flow left ventricular assist device. The Journal of Heart and Lung Transplantation. 2013;32(1):31–5. [DOI] [PubMed] [Google Scholar]
  • 14.Yanagida R, Czer LSC, Mirocha J, Rafiei M, Esmailian F, Moriguchi J, et al. Left Ventricular Assist Device in Patients With Body Mass Index Greater Than 30 as Bridge to Weight Loss and Heart Transplant Candidacy. Transplantation Proceedings. 2014;46(10):3575–9. [DOI] [PubMed] [Google Scholar]
  • 15.Zhigalov K, Sá MP, Arjomandi Rad A, Vardanyan R, Goerdt L, Chrosch T, et al. The Impact of Obesity on Left Ventricular Assist Device Outcomes. Medicina. 2020;56(11). [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 16.Butler J, Howser R, Portner PM, Pierson RN. Body Mass Index and Outcomes After Left Ventricular Assist Device Placement. The Annals of Thoracic Surgery. 2005;79(1):66–73. [DOI] [PubMed] [Google Scholar]
  • 17.Fonarow GC, Srikanthan P, Costanzo MR, Cintron GB, Lopatin M. An obesity paradox in acute heart failure: Analysis of body mass index and inhospital mortality for 108927 patients in the Acute Decompensated Heart Failure National Registry. American Heart Journal. 2007;153(1):74–81. [DOI] [PubMed] [Google Scholar]
  • 18.Lavie CJ, Alpert MA, Arena R, Mehra MR, Milani RV, Ventura HO. Impact of Obesity and the Obesity Paradox on Prevalence and Prognosis in Heart Failure. JACC: Heart Failure. 2013;1(2):93–102. [DOI] [PubMed] [Google Scholar]
  • 19.Bahrami MH, Mohammed A, Boyd C. Inotrope Dependent End Stage Heart Failure: Testing the Obesity Paradox. Journal of Cardiac Failure. 2017;23(8):S106–S7. [Google Scholar]
  • 20.Buchwald H, Avidor Y, Braunwald E, Jensen MD, Pories W, Fahrbach K, et al. Bariatric SurgeryA Systematic Review and Meta-analysis. JAMA. 2004;292(14):1724–37. [DOI] [PubMed] [Google Scholar]
  • 21.Sundaram V, Fang JC. Gastrointestinal and Liver Issues in Heart Failure. Circulation. 2016;133(17):1696–703. [DOI] [PubMed] [Google Scholar]
  • 22.Khawaja T, Chokshi A, Ji R, Kato TS, Xu K, Zizola C, et al. Ventricular assist device implantation improves skeletal muscle function, oxidative capacity, and growth hormone/insulin-like growth factor-1 axis signaling in patients with advanced heart failure. Journal of cachexia, sarcopenia and muscle. 2014;5(4):297–305. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 23.Jaiswal A, Truby LK, Chichra A, Jain R, Myers L, Patel N, et al. Impact of Obesity on Ventricular Assist Device Outcomes. Journal of cardiac failure. 2020;26(4):287–97. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 24.Caceres M, Czer LSC, Esmailian F, Ramzy D, Moriguchi J. Bariatric Surgery in Severe Obesity and End-stage Heart Failure With Mechanical Circulatory Support as a Bridge to Successful Heart Transplantation: A Case Report. Transplantation Proceedings. 2013;45(2):798–9. [DOI] [PubMed] [Google Scholar]
  • 25.Challappalli J, Cross D, Weber MP, Choi J, Maynes EJ, Aggarwal R, et al. Continuous-Flow Left Ventricular Assist Devices and Bariatric Surgery in Patients with Morbid Obesity and Heart Failure - A Systematic Review. The Journal of Heart and Lung Transplantation. 2019;38(4):S80–S1. [Google Scholar]
  • 26.Leviner DB, Keidar A, Ben-Gal T, Medalion B. Cardiac Function Recovery Following LVAD Implantation and Bariatric Surgery in a Morbidly Obese Patient. Journal of Cardiac Surgery. 2014;29(5):740–2. [DOI] [PubMed] [Google Scholar]
  • 27.Pullatt R, Crowley NM, Byrne KT, Axiotis D. Bariatric Surgery as a bridge to Cardiac transplantation in patients with LVAD. Surgery for Obesity and Related Diseases. 2018;14(11):S121–S2. [Google Scholar]
  • 28.Blumer V, Greene SJ, Ortiz M, Kittipibul V, Hernandez GA, Fudim M, et al. In-hospital outcomes after bariatric surgery in patients with heart failure. American Heart Journal. 2020;230:59–62. [DOI] [PubMed] [Google Scholar]
  • 29.Horwich TB, Broderick S, Chen L, McCullough PA, Strzelczyk T, Kitzman DW, et al. Relation Among Body Mass Index, Exercise Training, and Outcomes in Chronic Systolic Heart Failure. The American Journal of Cardiology. 2011;108(12):1754–9. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 30.Zenilman A, Pechman D, Moran-Atkin E, Choi J, Camacho D. Bariatric surgery in patients with left ventricular assist devices: a safe and effective method of weight loss as a gateway to heart transplantation. Surgery for Obesity and Related Diseases. 2019;15(10):1780–4. [DOI] [PubMed] [Google Scholar]
  • 31.Lee Y, Anvari S, Sam Soon M, Tian C, Wong JA, Hong D, et al. Bariatric Surgery as a Bridge to Heart Transplantation in Morbidly Obese Patients: a Systematic Review and Meta-Analysis. Cardiol Rev. 2020. [DOI] [PubMed] [Google Scholar]
  • 32.Hunt SA, Ea R. The REMATCH trial: Long-term use of a left ventricular assist device for end-stage heart failure. Journal of Cardiac Failure. 2002;8(2):59–60. [DOI] [PubMed] [Google Scholar]

Associated Data

This section collects any data citations, data availability statements, or supplementary materials included in this article.

Supplementary Materials

fS2

Supplemental Figure 2: Percentage of LVAD Patients Assigned to Either Bridge to Transplant or Destination Therapy based on Implant BMI

NIHMS1795211-supplement-fS2.tif (67.6KB, tif)
fS1

Supplemental Figure 1: Break Down of LVAD Patients via Implantation BMI, Treatment plan, and Transplant Success

NIHMS1795211-supplement-fS1.tif (82.8KB, tif)
fS3

Supplemental Figure 3: Movement To/From Transplant BMI of 35 After 6 months Based on Implant BMI for Patients with a Bridge to Transplant Plan.

NIHMS1795211-supplement-fS3.tif (204.8KB, tif)
fS4

Supplemental Figure 4: Movement To/From Transplant BMI of 35 After 6 months Based on Implant BMI for Patients on Destination Therapy

NIHMS1795211-supplement-fS4.tif (46.6KB, tif)
fS5

Supplemental Figure 5: Scatter Plot Demonstrating Weight change (kg) from 1 year prior to Implant to 6 months Post Implant Separated by BMI at Implant

NIHMS1795211-supplement-fS5.tif (206KB, tif)
tS1

Supplemental Table 1: LVAD Devices and BMI Changes by Device Type

NIHMS1795211-supplement-tS1.docx (13.8KB, docx)
fS6

Supplemental Figure 6: Scatter Plot Demonstrating Weight change (kg) from 1 year prior to Implant to 6 months Post Implant Separated by BMI at Implant from Bridge to Transplant Patients

NIHMS1795211-supplement-fS6.tif (387.7KB, tif)
fS7

Supplemental Figure 7: Scatter Plot Demonstrating Weight Change (kg) from 1 year prior to Implant to 6 months Post Implant Separated by BMI at Implant for Destination Therapy Patients

NIHMS1795211-supplement-fS7.tif (332.3KB, tif)

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